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Cummins approves B20 Biodiesel

  1. Apr 3, 2007 #1

    Ivan Seeking

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    http://www.biodieselnow.com/blogs/t...mmins-has-give-the-nod-to-b-20-biodiesel.aspx
    http://biz.yahoo.com/bw/070321/20070321005591.html?.v=1

    This is great news for the biodiesel market. It appears to apply to all blends up to B20, which would include all white and yellow locations here.
     
    Last edited: Apr 3, 2007
  2. jcsd
  3. Apr 3, 2007 #2

    brewnog

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    Eeeeeeeeeeeeeeeeeek! But oooooh.
     
  4. Apr 3, 2007 #3

    Moonbear

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    Can you mix fuels without gunking up the engines? In other words, if you're traveling across country, and start out in CA where there are tons of biodiesel pumps, according to that map, and then hit the middle of the midwest and are nowhere near biodiesel, will it be okay for the engine to fill up on regular diesel if you still have some biodiesel in the tank? If you can mix and match as stations are available, that's great, but if you need to stick with just one fuel type or another, then it'll be hard to get someone who needs to drive a truck cross-country to opt for biodiesel when they're going to hit long stretches where it just isn't available, or requires going out of the way and losing time to get to it.
     
  5. Apr 3, 2007 #4

    Ivan Seeking

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    B20 is a 20% mix of biodiesel with regular diesel. Fuels can be mixed in any ratio desired, or used as pure biodiesel. There are still some issues with running 100% bio in cold climates or if stored for long periods of time, so mixes provide a good option. Until now one of the biggest hurdles was that there were no fuel standards for bio and the many mixes used, but it appears that this is getting resolved.

    Edit: Yes MB, this solves the chicken and egg problem.

    Note that the State of Washington has recently mandated that diesel with sulfur addititives for lubrication be replaced with B2 - a 2% mix of bio with petro diesel - due to its superior lubrication qualities.
     
    Last edited: Apr 3, 2007
  6. Apr 3, 2007 #5

    brewnog

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    In other words, yes Moonbear, you can.

    A lot of people fill up with biofuel mixtures already without even knowing it, particularly in Europe. But even B20 is a pretty high blend for automotive uses; if this becomes freely available I would imagine some users with fuel systems other than those already approved may start seeing some problems. But all in all, good news.
     
  7. Apr 3, 2007 #6

    Ivan Seeking

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    What sort of problems? I know that the older engines had compatibility issues between the seals and bio, but most or all new engines are supposed to be immune. Another problem had been the lack of standards and testing. In the beginning, bio was often a mom and pop homebrew, but the industry has move far beyond that now. Another variable to be understood was the effect of the different saturated and unsaturated fats on fuel quality, which varies greatly as a function of the feedstock, but a good deal of progress has been made here as well.

    Of course, we don't see many diesel autos here yet.

    late edits
     
    Last edited: Apr 3, 2007
  8. Apr 3, 2007 #7
    It was also a good engineering move on Cummings part. In 2007 all new diesel engines will have to run on Ultra low Sulfur Diesel (ULSD) flue.

    This poses a huge problem of losing the lubrication properties of sulfur in the fuel for the injectors and pumps (just like the loss of lead in gas of the 70's on the valves of engines). Biodiesel of 2% or greater mixtures will have the same lubrication of pre ULSD (sorry I can't find the article, but I know it is somewhere in the EPA's or Department of energy website).
     
  9. Apr 3, 2007 #8

    brewnog

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    Yeah the main issue was always incompatibility with rubber/butyl seals within fuel pumps and lines. Manufacturers have tended to have ironed these out by trying to use materials like viton, but there are still some components on some engines which are still at risk.

    You also mentioned long-term storage. Generally, modern handling methods ensure that no problems should arise, but there is more risk of the fuel causing gumming within the engine, either as a result of chemical/biological degradation during storage, or due to the formation of residues during combustion. Here, components like injector needles and fuel pumps are at risk, with the potential for severe engine damage particularly with common rail (or other high injection pressure) systems.

    One other issue which I'm aware of is that biodiesel can be extremely effective at removing deposits and residues from fuel systems. This could be considered an advantage, but an engine which has run for a good while on petro-Diesel which is then switched to a high biodiesel blend could have a lot of these residues stripped from the fuel tank, lines, filter and lift pump, and find their way into the high pressure fuel system causing damage. The easy way around this is to ensure that you change your fuel filter soon after making the switch to biodiesel if you have an engine with any significant life already on it.

    Personally, I'd be more than happy to use B20 in pretty much any modern (4-5 year old) turbodiesel, providing I was happy of the source (and the new standards should help ensure this, although the recent Tesco/Morrisons issue may be a setback here), happy with the shelf-life, and happy to change fuel filters more often.



    Argentum, European diesel has been ultra low sulphur for a good while now, the engineering issues have already been overcome (largely, as you mention, by weak biodiesel blends).
     
  10. Apr 3, 2007 #9

    Ivan Seeking

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    Hopefully this move by Cummins will prompt the stragglers to get with it.

    This is partly related to the issue of fats. Feedstocks high in saturated fats are prone to clouding sooner at low temps. Conversely, feedstocks high in mono or polyunsaturated fats have shorter shelf life. What I didn't realize for a long time is that these problems - low temp clouding and shelf life - exist with regular diesel as well and this becomes as much a fuel management issue as anything - perhaps with seasonal blends as is done with petro diesel now. Also, I would expect that some bright chemists will find ways to improve on these issues.

    Sure, this is common knowledge now. Biodiesel is so clean and such a good solvent that it takes time to clean out the residue from that nasty old petro [B0] garbage. :biggrin: From what I've read, for engines that have run nothing but petro for a long period of time, this usually amounts to four or five frequent filter changes and you're okay.

    As for B100, I know that Willie Nelson is running his Mercedes on B100 made from cotton seed oil. You will also note a good number of B99/B100 pumps [blue dots on the map] along the west coast as a number of municipalities are using it for their vehicles; including the city of Portland busses. :cool: But the supply is still limited, so until B100 gains total acceptance, blends are a nice stepping stone that allows for a smooth transition away from petro.
     
    Last edited: Apr 3, 2007
  11. Apr 3, 2007 #10
    The reductions in sulfur in diesel fuel is killing engines right now. Guys are constantly having problems with it, it is to the point where mechanics are so sick of dealing with it that they are pretty well begging them to go buy fuel additives to improve lubrication.
     
  12. Apr 3, 2007 #11

    Ivan Seeking

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